The latter Wittgenstein argued that understanding does not consist in anything more than following a rule consistently. He criticized Socrates in The Blue Book, for being so obsessed with discovering the essence of knowledge that he refuses to look at Theaetetus’ examples. For a detailed argument against Wittgenstein’s view of Socrates, cf. Burnyeat 1977, Examples in Epistemology: Socrates, Theaetetus and G.E. Moore, pp. 381-383.